Neurological disorders such as seizure disorders are usually treated with medication. However, there are patients who are not helped by medication—they may not be able to tolerate the side effects or the medication itself is not efficacious for their particular disorder. This is a significant problem in that seizure disorders can be life threatening. Moreover, the quality of life for victims of severe epilepsy can be severely impacted. Neuropsychiatric disorders such as depression and ADHD are also typically treated with medications that have deleterious side effects and lack of efficacy. To offer patients relief that medication alone cannot deliver, various neurostimulation methods have been developed. For example, vagus nerve stimulation (VNS) has been shown to be therapeutically useful. Similarly, deep brain stimulation (DBS) and responsive neurostimulation (RNS) approaches are known to have efficacy. But these neurostimulation techniques are invasive as they require surgical implantation of electrodes. Thus, these techniques are relatively expensive and involve the dangers associated with the surgical implantation of the electrodes.
To provide neurostimulation without the invasive dangers of prior art techniques, an alternative neurostimulation therapy has been developed that involves trigeminal nerve stimulation (TNS). For example, a cutaneous embodiment of TNS involves the transcutaneous stimulation of the supraorbital nerves and/or the supratrochlear nerves in the forehead. Like other cranial nerves, the supraorbital and supratrochlear nerves arise through foramina in the skull. The supraorbital nerve arises from the supraorbital foramen above the orbit. Since one has two eyes, there are thus two supraorbital nerves that ascend vertically toward the scalp from their respective foramen. The supratrochlear nerve is medial with regard to the supraorbital. But it also then ascends vertically towards the hairline. There are thus two supratrochlear nerves, each arising from its respective orbit. A supraorbital nerve and supratrochlear nerve thus associates with each orbit. The forehead is thus an ideal location to stimulate the trigeminal nerve in that the supraorbital nerve and supratrochlear nerve associated with each orbit are located medially on the forehead. The skin and fascia over the forehead is relatively thin such that the supratrochlear and supraorbital nerves are readily stimulated transcutaneously.
Although TNS has shown great promise, there remains a need in the art to tailor TNS to particular disorders.